1. Field of the Invention
The present invention relates to polymers comprising betadiketone groups, to polymerizable compositions containing the said polymers and to a process for preparing polycyanoacrylate graft copolymers.
2. Description of the Related Art
The instant adhesive property of cyanoacrylate monomers results from the rapid polymerization of the monomer which is triggered by contact with traces of basic material. However, the resulting polymer has poor thermal stability and tends to degrade at temperatures above 70.degree. C. which leads to eventual failure of adhesive bonds. Various means have been suggested to overcome this problem, including synthesis of polyfunctional cyanoacrylate monomers (German Offenlegungsschrift No. 2141226 of Toa Gosei, (1972); U.S. Pat. No. 4,041,061 of Johnson and Johnson (1977), and European Patent No. 26,665 of Japan Synthetic Rubber (1981)), and the addition of putatively copolymerizable monomers (U.S. Pat. No. 3,692,752 of Matsumoto (1972) and French Patent No. 2121825 of Loctite (1972)).